Select the most appropriate ANTONYM of the given word.

Accustomed

Unusual

The correct answer is option 4. unusual.

"Accustomed" describes being familiar or used to something due to repeated exposure or experience. It implies a state of habit or routine.

The antonym "Unusual" is the opposite of accustomed. It means not familiar or common, something out of the ordinary or uncommon.

Therefore, in the context of antonyms, "Unusual" is the most appropriate choice as it represents the opposite of "Accustomed," indicating something that is not familiar or routine.